I don’t think this is weather related, I have had this car almost two years and that grinding/rattle has always been there. I hear it twice a week since I have owned it.

 

I believe it is weather related mine has been doing it since i bought it but only in the cold months. So has anyone mentioned it to their dealer yet? I will mention it when my tires come in if they ever do.

 

I believe one person had the car at the dealer overnight and was able to reproduce it. but i cannot recall what was done after that if anything. so if you are going to reproduce it at the dealer, you are going to have to leave her there overnight and then come back and start it up with the service manager there. good luck on that.

 

Wow, quite the long running thread, but exactly what I was looking for tonight. I have a six month old G35 Sedan with 15k miles, and it has been doing the timing chain rattle thing with increasing and annoying frequency. After a little bit of cajoling, I got a dealer tech on the phone who seems to know something about it, although he failed to mention the TSB to me -- go figure. . . I had called because it seems to be getting worse. FWIW, he told me that as long as the sound lasts only a second or so, it's OK. He said that if it goes on for more than ten seconds then it's a problem. Yeah, listening to timing chain rattle for 10+ seconds would probably both awaken the dead, and scare them too.

Has anyone actually had the repair done? I too am a little leery of letting the techs at the Infiniti place tear into my engine.

 

Ever since I got a new clutch put in my 350z there is a rattle on the cold start and also a grind or something when I'm at low rpm. I have no idea what it is. Manual transmission also. I've had oil changes and new oil filter also so it can't be that. Any answers??

 

I have this rattle on start up. I'm new to owning a Z but I picked one with every problem under the sun apparently lol. My question is, will this rattle set off the knock sensor. Everywhere I've taken the car to have the knock sensor code checked they say it's the rattling from the initial start that sets it off. The car's power isn't consistent either but it usually dies after the knock sensor code is set. I don't think to two are related but just curious if anyone else had this issue along with the rattle also.

 

I have the same issue,left it at dealer and they told me its the timing chain.it makez that rattle on cold days or if car is sitting over night.they said allot of them do this and it sometimes causes the knock sensor to come up on a code reader ..but nothing is wronv with the sensor..ive had my 03 auto for years and always have had this happen ,freaked me out when i noticed it ...but cant really worry about it too much if dealer isnt worried about it..

 

I've had this rattle for years. I think for various posters it is one - or more than one - of the following:

1) Timing Chain. There is slack there, and if the engine sits and oil drains from the bosses the rattle is impressive. I wonder if it is possible to 'pre-load' the chain against timing gears by releasing the parking brake after shutting down the engine, and allowing the Z to 'roll' against the resistance of the engine, pushing the crank and loading the timing chain. I haven't tried this; I'm just thinking out loud.

2) If certain oil filters have an check valve, it could leave more oil in the engine. This may solve the issue all by itself.

3) Valve train noise due to initial oil deprivation.

I gotta believe using the wrong type of oil filter is a big part of this problem.